Scotty, love your vid's, Im addicted.
We just purchased a 2004 SC430 with 49,000 on it. Obviously it was mint in and out. We had all the fluids changed and had Lexus check it out and they said all good and had all of the past records. My question is, do I need to change the timing belt and water pump? Do they go bad with age or just use/miles? PS, it runs and drives great and yes, the tires are new.
Welcome new member. Very insightful question (and great car). That is an interference engine, so if the timing belt fails, the car is totaled. So my suggestion would be to change the belt, and mazel change the water pump too while you are at it.
But maybe someone with direct experience with that engine says different.
Yup, mazel . 
Obviously it was mint in and out.
Not so obvious. Only a thorough inspection by a good mechanic can determine its true condition beyond cosmetics. The mileage is very suspicious for a car that age and hopefully it was verified.
My question is, do I need to change the timing belt and water pump?
Of course, if they're original. Rubber goes bad over a period of 20 years and the water pump should be changed out as well if driven by the timing belt. Best to replace ASAP to avoid serious trouble.
